Roller grinding-mill



(No Model.) 2 Sheets-Sheet 1. H. BOWMAN.

ROLLER GRINDING MILL. M -v Patented Feb. 18, 1890.

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HENRY BOXVMAN, OF ST. JOSEPH, MISSOURI.

ROLLER GRINDING-MILL.

SPECIFICATION forming part of Letters Patent No. 421,658, dated February 18, 1890.

Application filed November 25,1889- Serial No. 331,568. (No model.)

To all whom it may concern:

Be it known that I, HENRY BOWMAN, of St. Joseph, in the county of Buchanan and State of Missouri, have invented a new and useful Improvement in Roller Grinding-Mills, of which the following a specification.

My invention relates to roller grindingmills; and it is in the nature of improved means for regulating or adjusting the rolls with reference to each other, so as to render them parallel and also spring-seated or yielding to obstructions which may pass between them.

It consists in the peculiar construction and arrangement of parts for securing this adjustment, which I will now proceed to fully describe, and afterward point out in the claims.

Figure 1 is an end view of a port-ion of a roller-mill embodying my invention; Fig. 2 is a vertical section of the same through line a: w of Fig. 1, looking in the direction of the arrow. Fig. 3 is a detail side view of the frame A.

A represents one of the stationary end frames of the roller-mill. Outside of this is hung a hollow frame A,which carries a bearing for the journal B of one of the rolls B This hollow frame A has near its center a circular bearing a, which fits over a stud S, projecting from the main frame, and which stud serves as a support for this frame and also a center of adjustment. At the opposite ends of this hollow frame A there are disposed setscrews P P, which are tapped through lugs or flanges Z Z of the main frame and bear at their lower ends upon the upper side of the frame A upon opposite sides of its center. By means of these set-screws the said frame may be moved on its pivotal stud S and adjusted so as to level the grinding-rolls.

C is the companion roll to B and its j ournal O is carried in a bearing in a lever-arm L. This arm is of a somewhat right-angular shape and is contained within the chamber of the hollow frame A, being pivotally connected thereto by a stud D, which fits in thecircular hole Z7, Fig. 3, of frame A. The horizontal portion of this arm L is slotted vertically and is connected to a vertical screwrod I, having at its upper end a hand-wheel H for turning it. This screw-rod at K is screw-threaded and tapped into a corresponding screw-thread in the top portion of frame A. The rod I is turned one-eighth of an inch smaller in diameter immediately below K, I

When the red I is turned by means of its I hand-wheel, the differential effect of the-two screw-threads at K and M gives a very fine adjustment between the arm L and frame A, that causes the rolls 0 and B to approach or recede from each other according to the direction of the movement of the screw-rod, thus regulating the grinding set of the rolls. When the arm L is raised by nut M, the roll 0 is thrown away from the roll B and when said nut is lowered the rolls are brought together.

In combination with the aforementioned frame A and arm L, I employ a spring 0, composed of a number of fiat pieces of springsteel having a hole in each end and together forming a leaf sprin middle bears against a projection A of the frame A, and the ends of said spring are held up by screw-rods T and R, which extend through the holes at the ends of the spring and are each provided with a hand-wheel. The thread of the screw-rod T is tapped into the frame A, while the screw-rod R extends This spring at its up through the slot in the arm L and is tapped into a nut W, resting upon the top of the arm L. The tension of this spring is regulated by tightening of the screws T and R, and this tension in tending to pull down the arm L about its pivot 1) serves to press the roll 0 against the roll 13 with an elastic or yielding pressure. This permits the roll 0 to automatically move away from the other in case a nail, screw, or other hard and unyielding substance should pass between the rolls, the said rolls in that case yielding to permit the said foreign substance to pass without great damage to the rolls and the derangement of the adjusting devices.

In combination with the above-described device I also provide another spring-adjust ment, as follows: The arm L is extended above its roll C in the form of a vertical projection G. Through a hole in this proj ection passes a red X, having one end screwthrcaded and provided with a screw-threaded hand wheel or nut V, and a spiral spring U, coiled about said rod between the hand-wheel and the projection G. The other end of the rod X is connected loosely to a stud E on a hub or boss Z, having a rigid hand-lever Z projecting upwardly therefrom. Thishandlever has upon its side a spring-locking latch Z adapted to engage a notched segment Z This hand-lever Z is used to compress the spring U, so that while no interference is made with the grinding set of the rolls this lever and spring U serve to throw away the roll C from B in starting the machine or when running without feed. This is accomplished through lever Z by compressing the spring U until its tension is greater than the tension of the spring 0, at which time the rolls will separate, and upon release of the lever Z again they will "go together with the same set and same tension originally given them by the spring 0 and its ad justingscrews.

The hub Z is formed on the end of a shaft Y, Fig. 2, which extends across the machine parallel to the rolls, and is upon the opposite side of the machine provided with a similar set of connections for acting upon the exten sion G of another arm L on the opposite side.

In connecting the parts of the main frame and the frame A the inner end of the stud S on each sideis bored out and screw-threaded (see dotted lines, Fig. 2) to receive the screwthreaded end of tie'rod E, which extends across the machine from one stationary frame A to the other. The stud is provided with a hexagonal or angular head, so as to receive a wrench with which to turn it, and is cut away or reduced in size at F, so as to form a shoulder which bears against the main frame when turned to place. The parts are connected by first putting the tie-rod E in the stationary frames A and then passing the stud S through the hollow frame A and screwing it onto the ends of the tie-rod E hen turned up, the tie-rod connects the two sections of the main frame, and the frame A is hung loosely upon the'stud S between the shoulder F and the hexagonal head of the stud. The rod E may be further utilized as a support for scrapers for the rollers.

From the foregoing description it will be seen that while the rolls B and C have a yielding adjustment with reference to each other they are also both carried in the frame A outside of the main frame, and are together given an adjustment by set-screws, whereby the rolls may be leveled or trammed without disturbin the set of the grinding-adj ustment. The differential adjusting-screw I also permits of a very fine and delicate grinding set.

Having thus described my invention, what 1 claim as new is 1. 111021 roller grinding-mill, the combination of two rolls having independent bearings, springs for rendering one of them springseated or yielding to and from the other, movable frames sustaining both bearings of the rolls, a stationary main frame, and setscrews for adjusting the said movable frame upon the stationary frame, substantially as shown and described.

2. In a roller grinding-mill, the combination of two rolls arranged in bearings, one of which is made movable to and from the other, a springand adjusting devices located below the rolls for transmitting a regulated pressure to the rolls for a grinding set, and another spring and adjusting devices arranged above the rolls to antagonize the first spring and to separate at will the rolls without disturbing their grinding adjustment, substantially as shown and described.

8. In a roller grinding-mill, the combination, with the main frame, of a frame A, hung thereon and carrying one of the rolls, a leverarm L, pivoted or hung in frame A and carryin g the other roll, and the subjacent spring 0, hearing at its middle against a projection of frame A and connected at one end adjustablyto the lever-arm L by screw R, and at the other end to frame A by screw T, substantially as shown and described.

4. In a roller grinding-mill, the combination, with the main frame, of a hollow frame A, hung upon a projecting stud or hearing of the main frame and carrying one of the rolls, the lever-arm L, pivoted or hung to the frame A and extending inside its hollow chamber and bearing the other roll, and a spring and adjusting devices for rendering the arm L and its roller adjustable to the frame A and its roll, substantially as shown and described.

5. In a roller grinding-mill, the combination, with the roll B and its carrying-frame, of the lever-arm L, carrying roll 0 a spring and adjusting device for pressing the two rolls together, the said lever-arm being provided with an extension G, rod X, spring U, nut V, and adj Listing-lever Z for separating the rolls without disturbing their grinding adjustment, substantially as shown and de scribed.

6. In aroller grinding-mill, the combination of the two rolls, independent frames carrying the same, springs for forcing them together, and a differential screw for adjusting the rolls to each other with a fine adjust ment, one of the threads of the differential too ting the tie-rod, and a shoulder F, and the 10 carrying-frame for the roll-journals hung upon the said stud, substantially as shown and described.

HENRY BOWMAN.

Witnesses:

D. A. CLAUSER, O. A. HUBACHER. 

